I actually have 3 chicks I'm concerned with- 2 have the same problem and another is different. Hang in there with me while I explain.
One chick that I've been watching seems to be "balding" in certain areas. She is a Black Sex Link and I have 2 of them (same age), and the other looks nothing like this one, as far as baldness goes. I don't know if it's just the feathering process- losing fuzz and waiting for feathers to grow in- but I haven't noticed my other birds looking quite this bad. She is about 2 1/2 weeks old.
Next I have a Buff Orp and a Silver Laced Wyandotte (or Australorp- I'm sorry, I need to look up the breed pictures again, because I forgot which is which ) They are both 3 weeks old and missing tail feathers and I noticed because their rear end was bloody. Not near the vent, just the tail area and a little on the tips of the wings where they had touched the tail area. Are they being picked on or is something else going on?
Here are some pics:
First the "balding" sex link
Then the two with tail problems

I know this was a lot to post in one topic, so thank you to any of you who looked at the whole post. I had noticed the balding one yesterday or the day before, but the two with the missing tail feathers I just saw today when I was cleaning the brooder. I thought I might as well post it all together. Thanks again!

I have a sex-linked barred-rock that looked just like your first pic and he was so "ugly" I called him "Emu" (he looked like an emu). He is about 6 weeks old now and is the sexiest boy in the bunch. He feathered out beautifully. The other chicks with the bloody looking tail feather appear to have been picked on. The blood is from the newly formed feathers, called "blood feathers". Maybe it will pass. I know some parrots will pick their own feathers, but not sure if chickens do or not.

Some of the "funky" look is probably normal but I would check them all for external parasites while looking for the bird with blood on its face. You have a bully (or bullies) in the bunch. Separate any bird with visible injuries until they heal or they will be killed by the others (experience talking here). Make sure you have adequate space for the number of birds you have. You can try adding protein to their diet by giving scrambled eggs mixed with a bit of yogurt once a day.

I was thinking space could be the problem (at least for the two with pecked tails). I have them in the brooder still (well, brooder #2- we upsized once already) and the coop is not ready yet. There are 14 of them- mostly 2-3 weeks old, but I have 2 that are 5 1/2 weeks or so. The brooder is only about 4'x4' or so... Too small... I know. I had hoped for the coop to be ready sooner and have the 5 1/2 weekers out there by now and the rest soon after. I'm thinking its going to be about another 2 1/2 weeks for the coop but I will work on finding another large box to separate some into another brooder so they all have more room. Hopefully no bullying goes on tonight- they are quiet now, so I hope they're all sleeping. I'll get the second brooder going tomorrow.
I will also check them for parasites while I look over them to see if any others have injuries, etc. I held them all today and only noticed the ones I posted here, but just to be sure.
Thanks so much for the replies!

We had this problem also. We separated the bloody chicks as soon as we saw the damage. This happened to us twice, each time we kept them separated. We have a leghorn that at the time was becoming a pain. It was the only mean one we had and it seems to have calmed down. Thankfully this stopped and has not happened in a month. They all seem to be getting along well. I do know they are like mini raptors when they see blood.

Wow- you are a chicken healer! Great job nursing those chicks back to health. I'm glad to hear it all worked out.
As far as the older girls, I'm wondering if it's them at all. Everytime I go in there at night the younger ones are curled up to the big girls and some even try to get under them, and the big girls don't seem to mind at all. I even just went to check and the big girls were on thr roost and there was a little one on each side of them, practically under them. The big girls seem to be pretty mothering towards the younger chicks. I think it might be my "aracauna/EE" whatever she is (if she's a she). She has some blood near ner beak an from what I can tell there are no injuries on her, but it was only a tiny spot of blood, so I don't want to jump to any conclusions. I'm working on finding somewhere to separate the injured chicks or the big girls to see what happens.
So, as far as the blood feathers that are broken down close to the skin- do they just stay there? Will they fall out and allow for new feathers to come in? Do I need to do anything? I don't think there are any actual broken skin pecked spots- just the feathers pecked down to the skin. I'm not sure though, that's just what it looks like.
Thanks for all of your help and suggestions!